This book reviews and examines the chemistry of coumarin from different perspectives in six chapters. Chapter One reviews the one-pot synthesis of bromocoumarins via consecutive Pechmann condensation and bromination catalyzed by cellulose sulfuric acid. Chapter Two examines recent advances in heterocyclic compounds. Chapter Three looks at the chemical constituents and synthetic methods of bioactive coumarins. Chapter Four provides insights into the structure-activity relationship of alkylnyl-coumarinyl ethers as selective mao-B inhibitors using molecular docking. Chapter Five reviews the phytochemistry and pharmacological actions of coumarin. Chapter Six is an overview of coumarins from different perspectives.